Intraoperative sestamibi scanning in reoperative parathyroidectomy

BACKGROUND: Reoperative neck exploration for hyperparathyroidism is often difficult even for experienced surgeons. Recent advances in preoperative and intraoperative localization techniques have improved successful resection rates. This prospective study evaluates the accuracy and clinical utility of intraoperative technetium 99m sestamibi scanning for localizing hyperfunctioning parathyroid tissue in reoperative neck explorations. PATIENTS AND METHODS: Eleven patients underwent reoperative neck exploration for hyperparathyroidism. Two patients had 3 prior neck explorations, 1 had 2 prior neck explorations, and 8 patients had 1 prior neck operation. Preoperative studies included sestamibi scintigraphy and ultrasound in all patients, magnetic resonance imaging in 4, computed tomography scan in 3, parathyroid arteriogram in 1, and selective venous sampling in 1. All patients underwent intraoperative technetium 99m sestamibi scanning and parathyroid hormone assay. RESULTS: Preoperative technetium 99m sestamibi scanning and ultrasound each successfully localized 7 of 11 hyperfunctioning glands (64%). Intraoperative technetium 99m sestamibi scanning correctly localized 10 of 11 hyperfunctioning glands (91%). Intraoperative parathyroid hormone assay confirmed successful excision of hyperfunctioning tissue in all 11 patients. Postoperatively, all 11 patients had low-normal or normal calcium levels. CONCLUSIONS: Intraoperative technetium 99m sestamibi correctly localized 91% of hyperfunctioning glands compared with 64% localization for preoperative technetium 99m sestamibi and preoperative ultrasound. Intraoperative technetium 99m sestamibi scanning and parathyroid hormone monitoring are useful in reoperative neck explorations for hyperparathyroidism.     

[<Superscript>11</Superscript>C]choline PET/CT in prostate cancer patients with biochemical recurrence after radical prostatectomy

Objective  

To evaluate [¹¹C]choline positron emission tomography/computed tomography ([¹¹C]choline PET/CT) for the detection of a biochemical recurrence of prostate cancer after radical prostatectomy.     

Update on positron emission tomography for imaging of prostate cancer

Prostate cancer is the most common non‐cutaneous malignancy among men in the Western world, and continues to be a major health problem. Imaging has recently become more important in the clinical management of prostate cancer patients, including diagnosis, staging, choice of optimal treatment strategy, treatment follow up and restaging. Positron emission tomography, a functional and molecular imaging technique, has opened a new field in clinical oncological imaging. The most common positron emission tomography radiotracer, ¹⁸F‐fluorodeoxyglucose, has been limited in imaging of prostate cancer. Recently, however, other positron emission tomography tracers, such as ¹¹C‐acetate and ¹¹C‐ or ¹⁸F‐choline, have shown promising results. In the present review article, we overview the potential and current use of positron emission tomography or positron emission tomography/computed tomography imaging employing the four most commonly used positron emission tomography radiotracers, ¹⁸F‐fluorodeoxyglucose, ¹¹C‐acetate and ¹¹C‐ or ¹⁸F‐choline, for imaging evaluation of prostate cancer.     

Utility of [11C]choline PET/CT in guiding lesion-targeted salvage therapies in patients with prostate cancer recurrence localized to a single lymph node at imaging: Results from a pathologically validated series

ObjectivePositron emission tomography (PET)/computed tomography (CT) has been shown to be a valid tool in detecting lymph node (LN) metastases in men with biochemical recurrence after radical prostatectomy. We assessed its validity in detecting a single positive LN at pathologic examination in regard to an increasing interest in lesion-targeted salvage therapies.Methods and materialsWe included 46 patients with biochemical recurrence after radical prostatectomy and a single positive spot at [¹¹C]choline PET/CT who underwent pelvic or pelvic and retroperitoneal LN dissection. The ability of [¹¹C]choline PET/CT in identifying the exact positive LN was assessed with the positive predictive value (PPV) in the overall population and according to androgen deprivation therapy, prostate-specific antigen value, and site of PET/CT positivity.ResultsOverall, 30 patients (65%) had positive LNs at pathologic examination. Of these, only 16 (35%) had pathologically confirmed metastases in the same lymphatic region and 11 (24%) had involvement of 1 single LN. Conversely, 28 patients had positive LNs in other areas and 8 had no evidence of metastases. The overall PPV of PET/CT was 34.8% and 23.9% when exact concordance was defined according to the lymphatic landing site and single positive LN, respectively. The PPV ranged from 33.3% to 44.4% and from 17.9% to 28.6%, in men with and without androgen deprivation therapy, respectively.ConclusionsThe PPV [¹¹C]choline of PET/CT in correctly identifying patients with a single positive LN at salvage LN dissection is poor (24%). Therefore, extensive salvage treatment approaches are needed to maximize the chance of cure.     

Ultrasound and sestamibi scan as the only preoperative imaging tests in reoperation for parathyroid adenomas

BACKGROUND: In an effort to determine an efficient algorithm for the evaluation of patients with parathyroid adenomas in the reoperative setting, we explored the combination of using ultrasound scans (US) and sestamibi scintigraphy as the only preoperative imaging tests. METHODS: We analyzed the outcomes of 62 consecutive patients who were treated between January 1995 and May 1999 and who were referred for persistent primary hyperparathyroidism after initial surgical exploration, at which time no abnormal parathyroid glands had been found. Although all patients underwent US, computed tomography scan, magnetic resonance imaging, and sestamibi scan, we analyzed the success of localization and reoperation using only the results of US and sestamibi scan. RESULTS: Sixty-one patients (98%) underwent curative reoperations. The sensitivity, positive predictive value, and accuracy for US were 90%, 86%, and 84%, respectively; the corresponding values for sestamibi imaging were 78%, 94%, and 74%, respectively. In 58 of 62 cases (94%) preoperative US and/or sestamibi scan accurately identified the adenoma. In 3 patients for whom combined US and sestamibi scan were inaccurate, 1 adenoma was found by intraoperative US in the strap muscle; 1 adenoma was found by blind cervical thymectomy, and 1 adenoma was found by planned sternotomy that was based on computed tomography findings. CONCLUSIONS: This study supports an algorithm of obtaining US and sestamibi scan as the initial and perhaps only preoperative localization tests for patients with primary hyperparathyroidism after failed operation, at which time no abnormal glands had been found.     

11C-choline positron emission tomography/computerized tomography for tumor localization of primary prostate cancer in comparison with 12-core biopsy

PURPOSE: (11)C-choline positron emission tomography is an innovative imaging technique for prostate cancer. We assessed the sensitivity of positron emission tomography used together with computerized tomography for intraprostatic localization of primary prostate cancer on a nodule-by-nodule basis, and compared its performance with 12-core transrectal biopsy. MATERIALS AND METHODS: In 43 patients with known prostate cancer who had received positron emission tomography/computerized tomography before initial biopsy, we assessed sensitivity of positron emission tomography/computerized tomography for localization of nodules 5 mm or greater (those theoretically large enough for visualization) using radical prostatectomy histopathology as the reference standard. Comparison with transrectal ultrasound guided biopsy was based on sextant assessment of all cancer foci following sextant-by-sextant matching and reconstruction. Sensitivity/specificity of positron emission tomography/computerized tomography and magnetic resonance imaging for prediction of extraprostatic extension was also assessed. RESULTS: Positron emission tomography/computerized tomography showed 83% sensitivity for localization of nodules 5 mm or greater. At logistic regression analysis only nodule size appeared to influence sensitivity. At sextant assessment positron emission tomography/computerized tomography had slightly better sensitivity than transrectal ultrasound guided biopsy (66% vs 61%, p = 0.434) but was less specific (84% vs 97%, p = 0.008). For assessment of extraprostatic extension, sensitivity of PET/CT was low in comparison with magnetic resonance imaging (22% vs 63%, p <0.001). CONCLUSIONS: Positron emission tomography/computerized tomography has good sensitivity for intraprostatic localization of primary prostate cancer nodules 5 mm or greater. Positron emission tomography/computerized tomography and transrectal ultrasound guided biopsy show similar sensitivity for localization of any cancer focus. Positron emission tomography/computerized tomography does not seem to have any role in extraprostatic extension detection. Studies of diagnostic accuracy (as opposed to tumor localization) are needed in patients with suspected prostate cancer to see whether positron emission tomography/computerized tomography could have a role in not selected patients.     

Altered systematic glucose utilization after gastrectomy: correlation with weight loss

BackgroundAlthough gastrectomy induces weight loss and improves glucose homeostasis, the mechanism is not clearly elucidated.ObjectiveWeight loss after gastrectomy for gastric cancer may be the result from not only altered nutrition absorption but also systematic endocrinologic changes after bariatric-like surgery. No clinical studies have evaluated the altered glucose metabolism associated with postoperative weight loss in gastric cancer patients.SettingA retrospective analysis of a tertiary medical center.MethodsWe evaluated changes in ¹⁸ F-fluorodeoxyglucose uptake on positron emission tomography/computed tomography and weight change in patients who underwent gastrectomy. Participants comprised initially overweight (body mass index ≥23 kg/m²), who underwent ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography at 6 to 12 months after gastrectomy for early gastric cancer (n = 149). Small bowel, subcutaneous white adipose tissue (WAT), and skeletal muscle glycolysis were semiquantified using positron emission tomography/computed tomography. Measures were bifurcated or combined into values that correlated with ≥5% weight loss.ResultsWeight (median decrement, −3.3 kg), cholesterol level (−15 mg/dL), and body fat (−26.1%) significantly decreased after surgery. Substantial weight loss was significantly correlated with increased small bowel uptake of ¹⁸ F-fluorodeoxyglucose (≥5% weight loss versus <5% weight loss: 1.91 versus 1.69). Patients with an increased bowel uptake showed an increase in WAT uptake (P = .01). Patients with both increased small bowel and WAT uptakes were significantly correlated with weight loss (odds ratio: 9.67, 95% confidence interval 2.65–35.22).ConclusionsPatients with increased small bowel glycolysis and increased WAT uptake after gastrectomy are likely to lose weight. Altered glucose distribution contributes to improvement of the metabolic parameter after gastrectomy. We have shown evidence of bariatric surgery–like endocrinologic changes in gastric cancer patients who underwent gastrectomy.     

Radionuclide imaging for hyperparathyroidism (HPT): which is the best technetium-99m sestamibi modality?

BACKGROUND: To determine the utility of available radionuclide imaging modalities for preoperative parathyroid localization, we compared the accuracy of 4 types of technetium-99m ((99)Tc) sestamibi-based scans. METHODS: Over 5 years, 833 patients with sporadic primary hyperparathyroidism underwent either (99)Tc-sestamibi with planar views (Planar; n = 138); sestamibi single photon emission computed tomography (SPECT; n = 165); SPECT with thyroid (123)I-subtraction phase (SPECT/(123)I; n = 350); or SPECT combined with conventional CT (SPECT/CT; n = 180). The accuracy of each modality was determined on the basis of intraoperative parathyroid pathology, defined as single adenoma or multigland disease. RESULTS: Planar scans had significantly more false negatives (no tumor visualized) than SPECT-based scans (P < 0.01), but positive predictive values were similar. A false-negative scan was present in 38% of Planar scans, 27% SPECT, 4% SPECT/(123)I, and 17% SPECT/CT, with single adenoma found at operation in 77%, 64%, 53%, and 74%, respectively. When a scan had a single focus of uptake, SA was found at that location in 77%, 85%, 68%, and 87%, respectively. SPECT, SPECT/(123)I, and SPECT/CT did not significantly reduce the false-positive rate. CONCLUSIONS: We recommend obtaining multiplanar SPECT-based imaging, which offers 3-dimensional localization and improved detection of parathyroid tumors when compared with Planar scans. A negative scan did not predict multigland disease.     

Mild hypercalcemia: an indication to select 4-dimensional computed tomography scan for preoperative localization of parathyroid adenomas

Background

Technetium sestamibi scanning is the most accepted method of imaging used for preoperative localization of parathyroid adenomas. Four-dimensional computed tomography (4D-CT) scanning is a relatively new localization technique that has not been as rigorously evaluated.

Methods

One hundred thirty-five consecutive patients who underwent preoperative sestamibi scanning, 4D-CT scanning, and parathyroidectomy for primary hyperparathyroidism were evaluated. Patient characteristics, parathyroid gland weights, and the probability of having positive preoperative localization were examined.

Results

Four-dimensional computed tomography scanning was significantly more accurate than sestamibi (73% vs 62%, P = .016). In those with serum calcium levels less than 10.8 mg/dL, 4D-CT scanning was significantly more accurate than sestamibi scanning for the quadrant (45% vs 29%, P = .013) and hemisphere (66% vs 48%, P = .012). Also, 4D-CT scanning was more accurate among patients with parathyroid gland weights less than 500 mg (69% vs 45%, P < .001).

Conclusions

Four-dimensional computed tomography scanning provides better preoperative localization than sestamibi scanning, particularly in patients with mild hypercalcemia and smaller parathyroid adenomas.     

Sestamibi/iodine subtraction single photon emission computed tomography in reoperative secondary hyperparathyroidism

BACKGROUND: Sestamibi/iodine subtraction single photon emission computed tomography (SPECT) has been used successfully for the preoperative localization of adenomatous and hyperplastic parathyroid tissue in primary hyperparathyroidism, but the clinical usefulness of this technique in secondary hyperparathyroidism remains uncertain. The purpose of this study was to evaluate parathyroid localization that uses sestamibi/iodine subtraction SPECT in patients with secondary hyperparathyroidism before reoperative parathyroid surgery. METHODS: Fourteen consecutive patients with chronic renal failure and secondary hyperparathyroidism who had previously undergone total parathyroidectomy combined with parathyroid autotransplantation in a sternocleidomastoid muscle were studied. Before reoperation, each patient received 400 microCi of sodium iodide I 123 orally and 20 to 25 mCi of technetium Tc 99m ((99m)Tc)-sestamibi intravenously, followed by sestamibi/iodine subtraction SPECT of the neck and chest. At surgery, the location, weight, and histopathologic results of all identified parathyroid tissue were recorded. RESULTS: At surgery, 1 hyperplastic parathyroid gland was resected from each of 13 patients; including 1 undescended gland, 6 parathyroid autotransplants, and 5 mediastinal glands. The mean weight of the resected parathyroid glands was 1707 mg (range, 85-5300 mg). Sestamibi/iodine subtraction SPECT correctly identified and localized all 13 parathyroid glands (100% sensitivity) and was negative in the 1 patient whose surgery was unsuccessful. CONCLUSIONS: The (99m)Tc-sestamibi/(123)I subtraction SPECT is able to correctly localize hyperplastic parathyroid tissue in patients with secondary hyperparathyroidism who have previously undergone parathyroid surgery and is a clinically useful study before reoperation.     

Positron emission tomography/computed tomography differentiates resectable thymoma from anterior mediastinal lymphoma

ObjectiveDiscrete anterior mediastinal masses most often represent thymoma or lymphoma. Lymphoma treatment is nonsurgical and requires biopsy. Noninvasive thymoma is ideally resected without biopsy, which may potentiate pleural metastases. This study sought to determine if clinical criteria or positron emission tomography/computed tomography could accurately differentiate the 2, guiding a direct surgery versus biopsy decision.MethodsA total of 48 subjects with resectable thymoma and 29 subjects with anterior mediastinal lymphoma treated from 2006 to 2019 were retrospectively examined. All had pretreatment positron emission tomography/computed tomography and appeared resectable (solitary, without clear invasion or metastasis). Reliability of clinical criteria (age and B symptoms) and positron emission tomography/computed tomography maximum standardized uptake value were assessed in differentiating thymoma and lymphoma using Wilcoxon rank-sum test, chi-square test, and logistic regression. Receiver operating characteristic analysis identified the maximum standardized uptake value threshold most associated with thymoma.ResultsThere was no association between tumor type and age group (P = .183) between those with thymoma versus anterior mediastinal lymphoma. Patients with thymoma were less likely to report B symptoms (P < .001). The median maximum standardized uptake value of thymoma and lymphoma differed dramatically: 4.35 versus 18.00 (P < .001). Maximum standardized uptake value was independently associated with tumor type on multivariable regression. On receiver operating characteristic analysis, lower maximum standardized uptake value was associated with thymoma. Maximum standardized uptake value less than 12.85 was associated with thymoma with 100.00% sensitivity and 88.89% positive predictive value. Maximum standardized uptake value less than 7.50 demonstrated 100.00% positive predictive value for thymoma.ConclusionsPositron emission tomography/computed tomography maximum standardized uptake value of resectable anterior mediastinal masses may help guide a direct surgery versus biopsy decision. Tumors with maximum standardized uptake value less than 7.50 are likely thymoma and thus perhaps appropriately resected without biopsy. Tumors with maximum standardized uptake value greater than 7.50 should be biopsied to rule out lymphoma. Lymphoma is likely with maximum standardized uptake value greater than 12.85.     

Systematic review of the utility of 18-FDG PET in the preoperative evaluation of IPMNs and cystic lesions of the pancreas

BackgroundThe aim of this systematic review is to assess the role of 18-fluorodeoxyglucose positron emission tomography in the preoperative evaluation of intraductal papillary mucinous neoplasms and cystic lesions of the pancreas.MethodsA computerized PubMed search was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies evaluating positron emission tomography in the preoperative evaluation of pancreatic cystic lesions.ResultsA total of 14 studies evaluated the role of 18-fluorodeoxyglucose positron emission tomography/positron emission tomography-computed tomography, 9 of which evaluated only intraductal papillary mucinous neoplasms and 5 evaluated all pancreatic cystic lesions, including intraductal papillary mucinous neoplasms. Pooled analysis was carried out for studies evaluating intraductal papillary mucinous neoplasms only and studies evaluating all cystic lesions. Imaging with 18-fluorodeoxyblucose positron emission tomography had a positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of 90%, 91%, 85%, 95%, and 91% in identifying malignancy (defined as either invasive and/or high-grade dysplasia) in intraductal papillary mucinous neoplasms and a positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of 85%, 81%, 79%, 86%, and 88% in identifying malignancy in other cystic lesions. Pooled analysis reported the positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of Sendai consensus guidelines (SCG) criteria as 69%, 69%, 68%, 55%, and 58%. The Fukuoka consensus guidelines (FCG) only had sensitivity, specificity, and accuracy reported as 61%, 52%, and 52%, respectively.ConclusionThe 18-fluorodeoxyblucose positron emission tomography had a high degree of accuracy of detecting malignancy in intraductal papillary mucinous neoplasm and cystic lesion of the pancreas. Comparison of the utility of positron emission tomography with the Fukuoka consensus guidelines and the Sendai consensus guidelines suggest that positron emission tomography is superior to present guidelines in detecting malignant intraductal papillary mucinous neoplasm and cystic lesion of the pancreas. Further studies in larger patient cohorts may be required to corroborate these findings and to determine the place of positron emission tomography in the management of intraductal papillary mucinous neoplasm and cystic lesions of the pancreas.     

Parathyroid exploration in the reoperative neck: improved preoperative localization with 4D-computed tomography

BACKGROUND: Reoperation for hyperparathyroidism (HPT) carries an increased risk for morbidity and failure to cure. Accurate preoperative localization minimizes operative risk but is often difficult to achieve in the reoperative setting. Four-dimensional computed tomography (4D-CT) is an emerging technique that uses functional parathyroid anatomy for precise preoperative localization. We evaluated 4D-CT as a tool for localization of hyperfunctioning parathyroid tissue in the reoperative setting. STUDY DESIGN: A prospective endocrine database was queried to identify 45 patients who underwent reoperative parathyroidectomy after preoperative localization using 4D-CT. The patients were categorized into 1 of 3 groups: group 1 included those who had previous neck surgery for non-HPT conditions; group 2 included those who had undergone a previously unsuccessful neck exploration for HPT; and group 3 included patients with HPT who had a previous neck exploration with resection of at least 1 hypercellular parathyroid. RESULTS: The sensitivity of 4D-CT for localization was 88% compared with 54% for sestamibi imaging. Four-dimensional CT more often correctly localized (p=0.0003) and lateralized (p=0.005) hyperfunctional parathyroid tissue than sestamibi did. Four-dimensional CT successfully localized hyperfunctional parathyroid tissue in 18 (82%) of 22 group 1 patients, 10 (91%) of 11 group 2 patients, and 8 (67%) of 12 group 3 patients. Three patients were lost to followup. At a mean followup of 9.8 months, 39 (93%) of 42 patients were surgically cured and 3 patients (7%; 2 in group 3) had persistent HPT. CONCLUSIONS: Four-dimensional-CT is an ideal tool for preoperative localization of hyperfunctioning parathyroid tissue in the reoperative setting. Localization and successful reoperation are most difficult in patients who have undergone an earlier operation that included resection of at least one hypercellular parathyroid suggesting multigland disease.     

Is Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography Imaging Cost-effective in Prostate Cancer: An Analysis Informed by the proPSMA Trial

BackgroundBefore integrating prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) into routine care, it is important to assess if the benefits justify the differences in resource use.ObjectiveTo determine the cost-effectiveness of PSMA-PET/CT when compared with conventional imaging.Design, setting, and participantsA cost-effectiveness analysis was developed using data from the proPSMA study. proPSMA included patients with high-risk prostate cancer assigned to conventional imaging or ⁶⁸Ga-PSMA-11 PET/CT with planned health economics data collected. The cost-effectiveness analysis was conducted from an Australian societal perspective.Intervention⁶⁸Ga-PSMA-11 PET/CT compared with conventional imaging (CT and bone scan).Outcome measurements and statistical analysisThe primary outcome from proPSMA was diagnostic accuracy (nodal and distant metastases). This informed a decision tree analysis of the cost per accurate diagnosis.Results and limitationsThe estimated cost per scan for PSMA PET/CT was AUD$1203, which was less than the conventional imaging cost at AUD$1412. PSMA PET/CT was thus dominant, having both better accuracy and a lower cost. This resulted in a cost of AUD$959 saved per additional accurate detection of nodal disease, and AUD$1412 saved for additional accurate detection of distant metastases. The results were most sensitive to variations in the number of men scanned for each ⁶⁸Ga-PSMA-11 production run. Subsequent research is required to assess the long-term costs and benefits of PSMA PET/CT-directed care.ConclusionsPSMA PET/CT has lower direct comparative costs and greater accuracy compared to conventional imaging for initial staging of men with high-risk prostate cancer. This provides a compelling case for adopting PSMA PET/CT into clinical practice.Patient summaryThe proPSMA study demonstrated that prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) better detects disease that has spread beyond the prostate compared with conventional imaging. Our analysis shows that PSMA PET/CT is also less costly than conventional imaging for the detection of disease spread.This research was presented at the European Association of Nuclear Medicine Scientific Meeting in October 2020.     

Limitations of Tc99m-MIBI-SPECT Imaging Scans in Persistent Primary Hyperparathyroidism

Background  

In primary hyperparathyroidism (PHPT) the predictive value of technetium 99m sestamibi single emission computed tomography (Tc99m-MIBI-SPECT) for localizing pathological parathyroid glands before a first parathyroidectomy (PTx) is 83–100%. Data are scarce in patients undergoing reoperative parathyroidectomy for persistent hyperparathyroidism. The aim of the present study was to determine the value of Tc99m-MIBI-SPECT in localizing residual hyperactive parathyroid tissue in patients with persistent primary hyperparathyroidism (PHPT) after initial excision of one or more pathological glands.     

C-11-Methionin-PET/CT zur Lokalisation von Nebenschilddrüsenadenomen

Background and objectives

In primary hyperparathyroidism (pHPT) preoperative localization of parathyroid adenomas enables focussed unilateral parathyroidectomy. Ultrasound and sestamibi scintigraphy are the recommended standard procedures for primary diagnostics of pHPT and C-11 methionine positron emission tomography computed tomography (Met-PET/CT) is the latest technique for localization of hyperfunctioning parathyroid glands.

Methods

This review presents the results of Met-PET/CT on the basis of a selective literature search using the keywords “primary hyperparathyroidism and methionine”, “primary hyperparathyroidism and PET”, “parathyroid adenomas and methionine” and “parathyroid adenomas and PET”.

Results

Localization of single gland adenomas can be achieved with Met-PET/CT in 79–91?% of cases. The advantages of this procedure are a high sensitivity even in operations for recurrencies or concomitant thyroid nodules and an accurate detection even with atypical localizations. In multiglandular disease a localization of more than one hyperfunctioning gland remains difficult. Potential limitations of the method include the restricted availability and the relatively high costs of Met-PET/CT.

Conclusions

Using Met-PET/CT hyperfunctioning parathyroid glands can be exactly localized in most patients with pHPT. Indications for this procedure are mostly when preoperative standard tests are negative and in parathyroid surgery for recurrencies.     

Parathyroid hormone venous sampling before reoperative surgery in renal hyperparathyroidism: comparison with noninvasive localization procedures and review of the literature

OBJECTIVES: To analyze the predictive values of selective venous sampling (SVS) in our own experience and in a systematic meta-analysis of the international literature and to compare them with the results of noninvasive localization studies before reoperative parathyroid surgery. DATA SOURCES: Twenty-one consecutive patients with persistent or recurrent renal hyperparathyroidism underwent preoperative SVS and noninvasive imaging. These data were added to a systematic review of the literature on localization studies before reoperative surgery. The literature search included localization studies, recurrent hyperparathyroidism, and reoperation. STUDY SELECTION Prospective and retrospective studies that provided at least the true-positive rate of 1 procedure were included. Data from initial surgery, hyperfunctioning autografts, and case reports were excluded. DATA EXTRACTION: Thirty-one publications reported on SVS (n = 22), technetium Tc 99m sestamibi scintigraphy (n = 17), thallium-technetium scintigraphy (n = 11), ultrasonography (n = 18), magnetic resonance imaging (n = 12), and computed tomography (n = 13). The overall analysis was performed by dividing the overall number of true- and false-positive results by the total number of patients. DATA SYNTHESIS: Localization by SVS was correct in 20 of 21 patients. In 1 patient with 2 localizations, only 1 was predicted correctly. Therefore, the sensitivity of SVS was at least 90%, with no false-positive results. Overall true- and false-positive rates, respectively, in 31 studies were 71% and 9% for SVS, 69% and 7% for technetium Tc 99m sestamibi scintigraphy, 54% and 16% for magnetic resonance imaging, 55% and 15% for thallium-technetium scintigraphy, 50% and 18% for ultrasonography, and 45% and 14% for computed tomography. CONCLUSIONS: With its high sensitivity, SVS is the gold standard in patients with persistent or recurrent renal hyperparathyroidism and negative results of noninvasive localization procedures. The noninvasive procedure of choice is now technetium Tc 99m sestamibi scintigraphy, with high sensitivity and a low rate of false-positive results.     

Histological verification of 11C-choline-positron emission/computed tomography-positive lymph nodes in patients with biochemical failure after treatment for localized prostate cancer

OBJECTIVES

To evaluate the potential of ¹¹C‐choline‐positron emission tomography (PET)/computed tomography (CT) for planning surgery in patients with prostate cancer and prostate‐specific antigen (PSA) relapse after treatment with curative intent.

PATIENTS AND METHODS

We retrospectively reviewed the charts of 10 patients with PSA recurrence after either external beam radiation (two) or radical retropubic prostatectomy (eight) for prostate cancer, and who had a laparoscopic lymphadenectomy for suspicious lymph nodes detected on ¹¹C‐choline‐PET/CT. The histological results and PET/CT findings were compared.

RESULTS

In all, 22 suspicious lymph nodes were found on PET/CT, and 14 on conventional CT or magnetic resonance imaging. Comparing the conventional imaging showed concordance in 13 lymph nodes. Three of the 10 patients had no metastatic lymph node disease on definitive histology. The mean (sd ) PSA level for these patients was 1.0 (0.4) ng/mL, whereas that in patients with lymph node metastases was 15.1 (9.2) ng/mL (statistically significant difference, P < 0.05). The positive predictive value was seven of 10. All of the patients initially regressed, with PSA increases after lymphadenectomy. Two of the patients are being managed by watchful waiting, two had radiotherapy of the prostate fossa and two had chemotherapy with docetaxel. Four patients were treated by hormone‐deprivation therapy. After a mean (sd ) follow up of 11 (7) months, one patient died, one has PSA progression, but none of those with negative histology has clinical signs of local recurrence.

CONCLUSIONS

¹¹C‐choline‐PET is a valuable tool for detecting recurrent prostate cancer, but the limited positive predictive value should lead to a critical interpretation of the results.     

Value of <Superscript>123</Superscript>I-Subtraction and Single-Photon Emission Computed Tomography in Addition to Planar <Superscript>99m</Superscript>Tc-MIBI Scintigraphy Before Parathyroid Surgery

Purpose To find out if single-photon emission computed tomography (SPECT) and ¹²³I-subtraction can enhance the findings of ^99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy for the preoperative localization of parathyroid (PT) tumors. Methods Among the 111 consecutive patients who underwent preoperative planar ^99mTc-MIBI scintigraphy for hyperparathyroidism (HPT), 64 underwent delayed SPECT, and 17 underwent ¹²³I-subtraction. Two independent blinded experts scored the topographical localization, diagnostic confidence, and impact of each diagnostic modality on the surgical strategy. Results For adenomas, ^99mTc-MIBI scintigraphy had a sensitivity of 77% with a positive predictive value (PPV) of 83%. SPECT did not affect the sensitivity or PPV, but it increased the diagnostic confidence and changed the surgical strategy in 21% of the patients. ¹²³I-subtraction increased the sensitivity from 64% to 82%, but decreased the PPV from 88% to 82%. In hyperplastic glands, ^99mTc-MIBI scintigraphy had a sensitivity of 47% and a PPV of 95%. When ^99mTc-MIBI scintigraphy was combined with SPECT and ¹²³I-subtraction, the results were 44%/10% and 52%/92%, respectively. Both SPECT and ¹²³I-subtraction decreased the diagnostic confidence. Conclusions Adding SPECT to ^99mTc-MIBI scintigraphy improved the surgical decision for parathyroid adenomas. The addition of ¹²³I-subtraction was of limited value. For hyperplastic glands, ^99mTc-MIBI scintigraphy was relatively ineffective, even with the addition of SPECT or ¹²³I-subtraction.     

Is C-11 Methionine PET/CT Able to Localise Sestamibi-Negative Parathyroid Adenomas?

Background

Patients with primary hyperparathyroidism (pHPT) and a negative preoperative Tc-99 sestamibi (MIBI) scintigraphy are considered to have a higher risk of persistent disease. The aim of this study was to assess whether additional imaging with C-11 methionine positron emission tomography/computed tomography (Met-PET/CT) is able to localise sestamibi-negative hyperfunctioning parathyroid glands.

Methods

In 50 patients (38 females, 12 males, age 13–81 years) with pHPT and negative localisation procedures such as ultrasound and sestamibi, a Met-PET/CT was performed before parathyroid surgery. The results of Met-PET/CT were analysed prospectively and compared with intraoperative and histopathological findings. 22% of the patients underwent previous parathyroid and/or thyroid surgery.

Results

Met-PET/CT correctly located a single-gland adenoma in 33 of 45 (73%) patients with pHPT. In 5 patients with multiglandular disease, Met-PET/CT detected at least one hyperfunctional parathyroid gland in 4 patients (80%). In 3 patients with double adenomas, 5 of 6 parathyroids were correctly located. Overall, 40 of 57 (70%) hyperfunctioning glands were identified with Met-PET/CT. Met-PET/CT was false-negative in 12 of 50 (24%) patients and false-positive in only one case (2%). Postoperatively, 48 of 50 patients (96%) were cured.

Conclusions

Additional pre-interventional imaging with Met-PET/CT was able to identify hyperfunctioning parathyroid glands in 74% of patients with pHPT and negative sestamibi scans, thus enabling successful parathyroid surgery.